I have a fresh 350 crate motor with a flat tappet hydraulic cam in my pickup. The motor is broke in and due for another oil change. I am thinking of using Mobil 1 10w30 in it now , you guys think that would be a good thing. The motor was broke in with Valvoline 10w30 and ZDDP additive.

I like Mobil one in all my late model stuff, bikes, truck, wifes car. However, in my skiff with 350 with flat tappet solid cam I use the Brad Penn 10W30. It has the ZDDP in it. I did proper break in on this but I feel more comfortable using the Brad Penn. It is, I believe, semi-synthetic.

valvoline and Mobil 1 are both VERY good oils, about the best you'll find "off the shelf" in most areas.

If you have properly matched the honing process to a good set of rings then I'd use either now, if they still need some break in time I'd just stick with the valvoline- it certainly won't hurt anything.

I use both oils, and they're the only two brands I'll use. Good stuff.

Regular Mobil One 10w-30 does not have the proper amount of ZDDP for flat tappet camshafts. Using a ZDDP additive is not recommended by any oil manufacturer. There are plenty of oils now that are compatible with flat-tappet camshafts. Mobil One Racing oils, Amsoil Classic Z-Rod oils, Brad Penn, etc.

You need to use a SG,SH,SJ rated oil.
Most all the oil at the parts stores will be SM or SN and not suitable for older engines. SOmetimes, you can find motorcycle oil that has the correct API rating.
If it were me, I would use the Brad Penn.

I have a few flat tappet cams I have run fine without additives, on valvoline and Mobil 1. If its not a very aggressive cam it should be fine without it.

The other thing to remember is that ZDDP in itself is relatively meaningless. There are oils on the market that contain close to no ZDDP and can run a flat tappet cam just fine- they're made synthetic replacements for ZDDP.

Its always best to stay conservative (safe) but do some research into what you have and what you need- you may find that all the ZDDP hype is just hype in your case, or you may find it is an absolute requirement and need to get mail order oil.

Be sure to distinguish marketing and "my neighbor's best buddy" stories from facts too. I've heard of some neighbor's best buddies that have done some impossible things...

I have to agree with ap72 a lot of this info is hype. Take a look at this test Break-In Oil Please understand I'm not saying this test is gospel but I would think film strength of the oil would be a top choice when choosing an oil with a flat tappet cam. In this case if your looking for a value oil you can get the #9 rated 5W30 Chevron Supreme conventional, API SN = 100,011 psi film strength. I pay $12.99 for 5qt jugs at Bi-Mart. It beats most synthetics on the market.

Another interesting thing the film strength tests show is oil weight does not necessarily = film strength. I have also herd over at Bobstheoilguy that some weights in the same line of oil may be better than others. For example the 0w-20 may be the newest formula and may actual outperform the heavier weights.

(Disclaimer: i don't know jack about engines and am not a "natural engine person." Yet i manage to get hi mileage out of anything i drive. 300,000+)

For any cheapskates like me, who are still in the stone-age running flat lifters:

My thoughts on oil are as follows: The oil should be considered an integral part of the engine---the oil is a part just like the crank, rods, pistons etc. And not an afterthought. Therefore serious consideration should be given to oil selection and application.

Now, given the small price difference between running a ZDDP sufficient oil vs. whatever oil is on sale at the auto parts store---even if you change every 3000 miles (not even sure if that's still required these days), the difference in money is not that much, wouldn't it make sense to be safe and run a verified ZDDP sufficient oil? It's like cheap insurance.

That is my personal thought regarding oil for flat lifter engines.

i don't think mobil syn 10w-30 has enough. i think certain royal purple 5 and 10-30s have enough and redline 5 and 10-30's have enough.

I have to be picky on the oil I recommend. If a camshaft in an engine I build or machine fails because the oil used is not compatible with flat tappets, I get the grief. I will not stand behind an engine in which somebody has used something other than a dedicated, flat-tappet oil. Some can get away with using this or that, but I can't take that chance.

Before it was generally known that oil producers had reduced the amounts of high-pressure additives (zinc and phosphorus mainly) everybody was blaming camshaft and lifter manufacturers. Those companies really took a hit and replaced many components that failed through no fault of their own. Now that we know the whole story, things fall squarely on the shoulders of who ever is filling the crankcase. It's up to HIM or HER to become educated on this issue.

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